60 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The Trans-Pecos region is said to be poorly watered; the annual rainfall is prob- 
ably less than 20 inches (not over 13 inches at El Paso), and the streams are small 
and periodic in their flow. There are a good many springs in various parts of the 
region whose waters do not in every case reach the Pecos or the Eio Grande, but are 
lost in the ground or by evaporation. 
It thus appears that, climatically as well as geographically, Texas is almost all 
kinds of a State. While the coastal region receives an abundance of rainfall, there is 
a gradual decrease in the amount of precipitation as we go westward’. From a mean 
annual rainfall of 52 inches at Galveston on the coast, the decrease is more or less 
gradual until at El Paso, in the most western part of the State, the amount does not 
exceed 13 inches. The records also show considerable variation in different years, 
the amount sometimes falling as low as 10 inches in the western part of the State. 
The temperature of course varies greatly in different sections of the State. T ort 
Einggold, situated on the Eio Grande something over 100 miles above its mouth, has 
the reputation of being the hottest place in the United States except, perhaps, Port 
Yuma and Key West. The mean annual temperature at Fort Einggold is about 73°, 
at El Paso 63°. at Galveston 70°, and at Fort Elliott 54°. 
The prevailing winds are southerly or southeasterly, and blowing constantly 
across the State do much toward rendering the summers endurable even in the hottest 
parts of the State. 
VEGETATION. 
The flora of Texas is greatly diversified. In the northeast and eastern portions 
there are heavy pine forests, like those of the neighboring States of Louisiana and 
Arkansas. This does not extend, however, much beyond the Colorado Eiver, and 
only on its lower course.- In the vicinity of Galveston, or rather back from Galveston 
some miles, there is considerable timber along the streams and an occasional pine 
forest. Among the trees seen near Nicholstone are pine, three species of oak, elm, 
cedar, mulberry, ash, box-elder, hackberry, cherry, and holly; one of the most striking 
features of the flora here is the vast amount of Spanish moss ( Tillandsia usneoides) 
_ covering the oaks along Dickinson Bayou. Most of these species of trees were seen also 
about Houston. The pine forests, however, were more extensive about Houston and 
along Clear Creek, where were to be seen a good many magnolias and an occasional 
persimmon tree. The Spanish moss was less common here than at Nichols tone. 
The Black Prairie belt has few trees except along the streams, where there is a 
good growth of cottonwood, pecan, cypress, oaks, and numerous species of shrubs. 
About San Marcos, New Braunfels, and San Antonio these trees are abundant. The 
oaks and other trees situated in the valleys along the streams were thickly overgrown 
with Tillandsia usneoides , but on the higher lands about New Braunfels and between 
San Antonio and Corpus Christi there are considerable clumps of oaks which are pro- 
fusely covered with another epiphyte, Tillandsia recurvata. West of the Black 
Prairie the timber is scrubby and of little value except for fuel. The river valleys do 
not differ materially from those parts lying in the Black Prairie region. 
Below El Paso the valley of the Eio Grande widens out into a great plain, which 
is covered near the river with cottonwoods, willows, and a species of ash.* On the 
*Most of tlie facts regarding the vegetation of this region have been taken from Dr. Havard’s 
valuable Report on the Flora of Western and Southern Texas. -Proc. U. S. Nat. Mus., 1885, 449-533. 
